1. Hepalatide
Hepalatide is a polypeptide disclosed in Chinese application No. 201010174788.X, the amino acid of which is set forth in SEQ ID NO: 1 of the Chinese application and also in SEQ ID NO: 1 of the subject application. The N terminus of the polypeptide is modified by myristic acid and the C terminus is modified by amidation. Hepalatide can effectively block the infection of liver cells by hepatitis B virus.
The amino acid sequence of Hepalatide is derived from the HBV large surface protein, which was known to assemble to form particles of 23-120 nm in vitro (Kuroda S, Otaka S, Miyazaki T, Nakao M, Fujisawa Y., Hepatitis B virus envelope L protein particles. Synthesis and assembly in Saccharomyces cerevisiae, purification and characterization, J Biol Chem. 1992 Jan. 25; 267(3):1953-61).
2. Current Status on Research of Formulation of Polypeptide Drug
Polypeptide drug consists of amino acids which connect in series. Different combinations of amino acids make the polypeptide to have unpredictable spatial structure and physical and chemical properties. Important pharmaceutical properties of the polypeptide, such as solubility, stability, ionization and pH, etc., are more easily to be affected by the surrounding environmental solution than the small molecular drug. In the meantime, there are significantly different specific conditions and requirements on clinical use of different polypeptide drugs, and strict requirements on the drug formulation by the in vivo environment. As a result, the results on studying formulation of polypeptide drug are difficult to be predicted and dosage form and prescription for a specific polypeptide drug have to be explored through prescription screen. Hepalatide is a polypeptide drug newly developed by the inventor, thus currently there are no published reports about study on formulation of Hepalatide.